Disk brake



J. C. M CUNE Jan. 19, 1954 DISK BRAKE 2 Sheets-Sheet 2 Original Filed Aug. 12, 1948 6088 86 88 92 INVENTOR.

Joseph C MeCune ATTORNEY 3 of the rings l8, said rings merely acting to hold said shoes assembled to the driving lugs l2. It will be further apparent that the two rotors 29 and 2| are slidable on the drive lugs i2 in a direction parallel to the axis of wheel I, axle 3 and the brakehub 6.

In each of the ribs |5 there is a bore 22 extending parallel to the length of the rib between the opposite guide surfaces i6 thereof and opening through a slot 22a to the outer face of the rib. The end of each bore 22 adjacent to wheel I is closed by a plug 23. The ring l8 mounted on the side of rotor 20 opposite the'wheel is provided with a plurality of stop fingers 24 extending through the respective slot 220. into each of the alternate bores 22, while the corresponding ring of rotor 2| is provided with like fingers 25 extending into the other bores 22.

In each of the bores into which the fingers 24 project there is interposed between said finger and the respective plug 23 a rotor release spring 25a bearing at one end against said plug and at the opposite end against one side of a follower 26 slidably mounted in the bore and having its opposite side in contact with the respective finger 24. At the opposite side of each finger 24 there is a stop pin 27 whichadjacent the end opposite the wheel I is provided with a circular recess arranged to align with a slot in the outer surface of the respective rib l5 at either side of slot 22a,

and encircling the several guide lugs 13 within said slots therein and within the recesses of the several stop pins 21 is an expansible retainer ring 28 for holding the several stop pins 2| in place. The two ends of the ring 28 are bent inwardly and tied together by a wire band 29 for holding said ring against moving out of the slots by centriiugal force upon rotation of the driving lugs l2 with the wheel I. The springs 25 are under pressure for urging the fingers 24 against the stop pins 21 which act to define the brake release position of rotor 29.

A release spring 39 is disposed in each of the bores 22 into which the fingers 25 of rotor 2| project. One end of each spring 39 is supported on the respective plug 23 while the opposite end bears against one side of a follower 3|, the opposite side of which bears against the respective finger 25 which is adapted to engage ring 28. The several springs 30 are under pressure for, through the medium of fingers 25, urging the rotor 2| to a brake release position defined by contact between said fingers and the ring 28. A cotter key 32 is secured in the wall of each of the bores 22 into which the fingers 25 of rotor 2| project, adjacent the end of said bores opposite the plugs 23, for engagement by the respective spring followers 3| when the ring 28 and rotor 2| are removed from the drive lugs I2 to prevent said followers being moved out of said bores by springs 30. No means such as key 32 is required in the other slots for the followers 26 therein will still be in their bores upon full expansion of the respective springs 25a.

The brake hub 6 carries two anti-frictional bearings 33 held in spaced relation by spacers 34 and secured to said hub by a retainer nut 35 having screw-threaded engagement with the end of said hub. Mounted on these bearings and thereby journaled on the hub 6 is a bearing housing 36 provided around its exterior surface with a plurality of outwardly extending lugs 31. En-

1 circling the housing 36 is a combined stator and brake cylinder supporting ring 38 rigidly secured around its inner edge to the lugs 31 by bolts 39,

said ring being disposed at the side of rotor 2i opposite the wheel I. The housing 35 and ring 35 are adapted to be held against rotation by any suitable torque means (not shown).

Disposed at the side of rotor 29 adjacent wheel I is a stator retaining ring 40 encircling the axle 3 and Wheel hub 4 and in concentric relation therewith and with the stator and brake cylinder supporting ring 38. Rigidly secured at one end to the retaining ring 40 and projecting therefrom into contact With the adjacent surface of ring 28 are a plurality of tie bars 4| equally spaced from each other, and extending through the latter ring and through each of said bars and having screwthreaded engagement with a nut 42 secured to the ring 40 is a bolt 43 for rigidly securing the ring 40 to and for holding it in a predetermined spaced relation from the ring 38.

The tie bars 4| are preferably square in section having opposite parallel sides 48 arranged generally parallel to the radii of rings 38 and 46.

Mounted against the side of ring 58 opposite the ring 40 are two equally spaced apart substantially semi-circular brake cylinder devices 44 which are secured around their outer edge to the ring 38 by the bolts 43 and around their inner edge by a plurality of bolts 45 secured at one end to the ring 39 preferably by welding and having on their opposite end a nut 45 engaging the brake cylinder device.

Mounted against the stator and brake cylinder supporting ring 38 between said ring and rotor 2| is a pressure ring 49 having a plurality of spaced apart slots 59 open to the outer edge and in which the tie bars 4| are disposed with the sides of said slots in sliding contact with the sides 48 of said tie bars whereby said ring is slidable on said bars in a direction toward and away from said rotor. Projecting from the side of the pressure ring 49 opposite rotor 2| through suitable openings 50a in the brake cylinder and stator support ring 38 are spring anchors 5| to each of which is connected one end of a stator release spring 52. The opposite end of each spring 52 is connected to a wire bail 53 at its center, the opposite ends of each bail being bent parallel to the axis of the spring and being disposed in openings provided in webs 54 of the brake cylinder devices 44.

Disposed between the pressure ring 49 and rotor 2| is a non-rotatable brake element or stator 55, disposed between the rotor 20 and the stator retaining ring 40 is an identical but oppositely arranged non-rotatable brake element or stator 56, while between the rotors 20 and 2| is disposed a third non-rotatable brake element or stator 51.

The brake stator 51 comprises two relatively thin, flat-sided metal rings 58 each of which is made up of ring segments 59, corresponding in number to the eight tie bars 4|, and arranged in substantial end to end relation. The segments 59 are rigidly secured together by bridge pieces 60 overlapping adjacent segments and secured thereto by welds 6| except at two diametrically opposite connections which are effected by bolts as will be hereinafter described. It will thus be seen that each stator ring 58 is built up in two separate and geeses ettith lioles 63 forthe hereinafterd b f 'twcrseniiae-irdulm; p r ring 7 secured' by"welding to-'ones ide and adja'cent used atthe end' of the I "to the -'inn 'er."edge 10f each segrr iient fis are three" spaced apart friction" brake shoes-M for frictional braking contact with the" adjacentbrakingface "fofrotor-M or H. t 'E-ach -'of'the *brakeshoesfid provided with two spaced. radially extending 'jthe radialductsf B5 2: said .duc'ts' 'bei'ngfo'pento" the .g jace; of'the" shoe adjacent the r n 58' and being I i'provideditopermitcirculation {of air currents'rto dissipate heatTr'om theshoe'"incidentftotbraking.

-., :Eachpf, thawing, segmentsj'59jisi also"fprov'ided (,iriidW'ayj between"lits ends fiwith a "parallel; sided ;T. s1ot'61,.open -td the outer 'edge 'thereof ito receive .onefof the tie bars'4'I ju'pon all ofwhich'fthestator .1I51=,is. mounted to" slide, axially.

be n to .backwith the, brake shoe'j'fi lfanfd bridge ipiecesl'fifl. on the outer or opposite ffaces jand j-thetwo semi-circularparts of eaeh 'ringareriig- Qidly secured, at each end- .toi each other. and "to ,the correspondingiparts .ofjthe other. ring by twobolts 68 extendingthroughthe alignedholeslfl in the adjacent ring segments 59 and overlying ends of the respective" bridge pieces 60, it being notedgthatr while; only-,- onebolh I58 is i required at ch tend-to: connectfiogether two halveswof ithergone of'the; ringslthatrtwogbolts .68 are reuiredifor; twow rings;v arranged back to back as also-extend beyondztheaout'eriedge 'ofztheirings. nd in itthe-fie-xtending portioniithereof: eachrzof these clips is provided 'wi th(az'slote nextending radially? of the .1 stator into 5th ip ga'xchosen stance n one legofi-the 'elip and to' va-ibore through thefiother leg.

2 ch 2 I w ithleaoh ofi thettieibars' 4 Iedi'sposed -=-'-in th alignedslotsze'b 'ot Dneiipair: of: sbackizto J iran'ged ring segmentsa59; said barsaacarry- *ing strid statora'nd h'aving' -sliding contactuwith the side walls of said slots aiid witlttheelegsiiof' the respective clips .69, orJl, the bore 13 in the clips II being disp'os'edatthe side of the stator ;x;9pnosi;te,.the rotori I. H emovablelugs the brakecylinder devices 44 by, the b'oltsl43, a ovyelpin II 5 carried. .by. said i webs cooperating with said lugs for locating samer Se'curedfat oneend to; the outereend lof-iea'cli lug 1114. and I ring: iifi hy-a cotter key Qaextending'dhrohgh wheel I .and ifOl therefore :,.defining;:.a. .brake-;rei lease po'sitionof- Said: stator. 'sslid'ably, mounted in eam-stop elementmfi is a plunger 'l'l'sse'cured w oneend of a fiexiblec'ablei lfi extending through preferably punched from sheet metal on the .{l li aligned- .iwit the ioli ps e r gidly. clamped to the outer webs .54. of

ment: oi the, stator. 511m.thegdireetion awawfrom eception of a: belt to he =7 Wand connected at the opposite 'end toi tained in'each stop member 'lfi bears-at one *-en againstthe plunger11= while-' its opposite e leg-'around the' slot 12' therein. 1 spring '8ll conextends. 1 The --springs 8 9- am under pressuremid through the =me'diumof the *respcti-ire cttblesi-i 8 -and buttons 19 are adapted to 'a'ct on the' eiips """I' I for constantly pullingthe rotore'l' to its-brake they'are' securely held -therein by springs' 80? release-position. I

'J With the tbuttons' 7 9 disposed "in -th hb'le's 13 'ofl'oneileg'of clips 'I I it will be apparent that ajch button 79 is provided with an externalj knbb fl "j for a. workman to grasp'fox-"pulling said button out of; the iholefls'gagainst the force or spring-{80 'Jand'for then "moving cable-I8 outwardly through "the ;slot 7 2 for-disconnecting the button 'froifi the jcl'ip"1l. "I'Ihe'endof each stopelemhtFWB opposite' thatprovid'ed for engagement by the reventing entrancei'iof foreign matter into? said stop.

The stator et'comprisesa ring85 made up of segments 8 rigidly securedtogether into two semi-circular parts .by "welding of"'bridge-'-pieces Gil; the ends' of the" two parts'being rigidly secured together to form'a solidringfby ai siiifgle bolt 87 at each endextending"throughitheoverlapping bridge pieee'tg of'one partahdthering segment 8% of the othertpa'rt. The'j"-stator?re- .gethen' .Thelseg'mentsfle' and bridge pieces fifl are identical to the segments 59 and'bridg'e' pieces v{i employed. the stator" except "that said 7 segments are made of slightly thicker metal.

---We1ded to the samesicie of each of 'thev'ring s-segmentslfit as engaged. by the bridge pieces are threespacedapart brake shoesfis which are nidentical to the brake shoes 6d on"st'at'or 593x- -s-cept less the airducts f;andii$.

1 I -outer edge for receiving .one' of the jtie;bars'""4l, -51 is -imountedribetweenetheirotors which'bars coasting With'allof .the segmentsBG The segments as andfit of the stators'5'l; Stare same; press, and at each side of the slotilBJiTQO therein there is provideda h 1 ;9l have no function in the statorffi'kbut inthe These holes stator 56 four of theseholes,..vequa"11y" spaced gap-art, 'are'adapted to receivelugs'ez welded-gm one end to theretainer ring demand whichextend through the holes. Mounted over each-.joi'

\ the lugs -92 :against ring 851s .a: spring washer '2: 931whichis held under compression againstlthe the-lug. The purpose of this -construction.is,;to

.hold athestator 55 :against chattering on. .the

' retainerringrte when the stator 57 is outer-contactxvith the-adjacent rotorifi.

The stator 55 is the same inconstruetion'aas holding the stator against turning relative to said saiid -elem'ent-into slot 12 in 'theresp'ective clip; 57:; bars, ;and.. .lugs 92 .:pr0j ecting from the pressure The two brake cylinder devices 44 may be identical, oppositely arranged, and somewhat less 7 than semi-circular structures, one located above and the other below a horizontal plane including the axis of axle I. Each of the brake cylinder devices comprises six equally spaced apart cylinders 94 the bores 95 of which (only one being shown in the drawing) are open at one end to the adjacent face of the stator and brake cylinder supporting ring 38, with a gasket 99 interposed between said ring and the adjacent end of said cylinders for excluding foreign matter from the bores 95.

Slidably mounted in each of the bores 95 is a piston 98 between which and an integral cover 91 for the opposite end of said bore there is provided a pressure chamber 99. At the opposite side of piston 98 is a non-pressure chamber I09. Projecting from the piston 98 through the nonpressure chamber I is a piston rod I82 the end of which, opposite that connected to piston 98, contacts the adjacent face of the pressure ring 49.

.A brake release position of the brake cylinder piston 98 is adapted to be defined by engagement of said piston with a stop lug I91 provided on cover 91, and in this position, the release position of the pressure ring 49 may be defined by engagement of an outturned flange I88 at the inner edge of said ring with the stator and brake cylinder support ring 38.

In each brake cylinder device 44 the brake cylinder cover 91 is provided with a raised portion containing an air passage I99 extending over the several cylinder bores 95 and open to each of said bores by a passage III), the two air passages I99 being adapted to be connected to any conventional brake controlling valve device for controlling supply and release of fluid under pressure to said bores and thereby pressure chambers 99.

In operation, assuming that the several brake cylinder pressure chambers 99 in both brake cylinder devices 44 are open to atmosphere, the several springs 52 connected to pressure ring 49 will hold the flange I08 of said ring in contact with the support ring 38 and thereby hold the several brake cylinder pistons 98 in substantial contact with their stop rib I91, thereby positioning both said pistons and the stator 55, which is secured for movement with the pressure ring 49, in the brake release position. With the stator 55 thus positioned the springs 30 will move the rotor I1 to its brake release position in which it is shown in the drawing spaced away from the stator 55, and the springs 89 connected to the center stator 58 and springs a acting on rotor 29 will position said stator and rotor in their brake release position as shown in the drawing and in which they are disengaged from the brake elements at either side thereof.

Now in order to render the brake mechanism effective to brake wheel I fluid under pressure will be supplied to the brake cylinder pressure chambers 99 in both brake cylinder devices 44. When the pressure of fluid thus obtained in chambers 99 and acting on the pistons 98 in opposition to springs 52 becomes increased to a degree sufficient to overcome said springs, said pistons, through the medium of rods I82, will slide the pressure ring 49 and thereby the associated stator 55 along the tie bars 4| into contact with the rotor 2|. Further movement of the pistons 98 will then slide rotor 2 I. along ribs I5 on the guide lugs I2 into contact with the central stator 51 and then slide said stator along the tie bars 4| into contact with the rotor 29 which then will be moved along said ribs into contact with the end stator 56, the several stators being thus urged into frictional contact with the opposite sides of the two rotors 29 and 2| which will create a dra on said rotors to effect braking of wheel I to a degree determined by the pressure of fluid provided in the brake cylinder pressure chambers 99. Any desired degree of braking of wheel I may be obtained by providing the proper pressure of fluid in the brake cylinder pressure chambers 99, as will be apparent.

When it is desired to release the brakes fluid under pressure will be released from the several piston chambers 99, whereupon the springs 52 willreturn the pressure ring 49, and thereby the stator 55 and the several brake cylinder pistons 98 to their release positions, during which move ment, springs to, 30 and 25a will return the stator 51 and the rotors 28, 2| to their brake release positions in which they are shown in the drawing and in which they are disengaged from each other, in order to permit free turning of the wheel I.

Maintenance In order to replace any one of the stators 55, 55 or 51 or to renew the brake shoes I1 in the rotors 20, 2|, the bolts 43 extending through the tie bars 4| will be removed as well as the bearing retainer nut 35 whereupon the brake cylinder devices 44 and the support ring 38 therefore may be moved back on the axle 3 away from the other parts of the brake apparatus.

The pressure ring 49 and connected stator 55 can then be pulled off the tie bars 4| and the stator removed from said ring and replaced with a new stator. In order to renew the shoes on rotor 2| all that is then necessary is to remove the bolts I9 securing the rotor rings I8 to opposite sides of said shoes whereupon said shoes can be replaced.

In order to renew the stator 51 it will be necessary to cut the wire band 29 holding together the adjacent ends of ring 28 and then remove said ring from the rotor drive lugs I2, whereupon the rotor 2| can be removed. The stator 51 can then be removed from the axle by removal of bolts 68 and replaced by a new stator, and if desirable the shoes I1 of the rotor 20 can be renewed in the same manner as the shoes of rotor 2|. Also, the stator 56 can then be replaced if desirable following which all the parts can be reassembled in the reverse order.

Summary It will now be seen that I have provided a disk brake mechanism embodying rotatable and nonrotatable brake elements, or rotors and stators respectively, which are rugged but relatively simple and inexpensive to construct and which may be readily repaired or replaced.

Having now described the invention, what I claim as new and desire to secure by Letters Patent, is:

1. A brake disk for a disk brake apparatus comprising a plurality of disk segments arranged in substantial end-to-end relation, one or more brake shoes secured to each of said segments, a bridge piece overlying adjacent ends of each adjacent pair of segments and welded thereto except at two connections between two bridge pieces and segments arranged at diametrically 91 i 012p si-te nariss;cnazsaid.rdisksneach o said; br e; pieces: :lrlav-i-n :two: spaced; apartbores :ior align ment, with {bOTESiIIithGI underlying; segments; and; r a iboltzinethe :a1-ig:ncd -.:bores 1 in. therbridge p eces together: i

2.: s A non-rotatable ibrakesdisk "for usezeitherias: an;interm-ediate =zor rend stator; of; a pile -;of, :inter.: leavedarotatableandanonerotatableibrake disks; 1' i, comprising .a pluralityfor;segmentsaarranged; irrzJ substantial-1endrtoeend:;1'elation,:;..one;1 ,"OIKJITLOI' br.a-ke',.-shoes-j securedronone race; of each ;of;said segments adj acenta the; inner :iedge; =thereof ,-r-a bridge; piece overlying; adjacent; ends-i of; each adjacent pair of; segments? andgzweldedhereto x1 Xcept-"at wo: connections: between-awo- :bridge: 1-: pieces- ;and.-;segments arranged diametricallyqppe; posite on said disks, each of said bridge pieces having two spacerirapartbores folvregistryqvith boresdnthe underlying scgmentsto receive bolts at the unwelded'connectionsza slot injeachseg I merit: adjacent the outernedge thereof, and a hole throu h each segment, at, each :of ;1the opposite, sidespi the-slots therein;-

3.wA,--non-rotatable brake: element for ta ,disk J brake apparatus comprising a pairotcoaxially arran ed ringlikeemeans arranged in back-toe; back relation i a plurality of. segmental brake shoesisecu-redrin spaced apart relation to each of the opposite"fac'esiof saidpairwof ring-like ,30 means, a plurality of spaced apart slots in each oftha two ring-like means having opposite, pare allel, ear side'wallsextending generally radially ofthe-ringdike means and aligned with thewear tending over: theopposite sides-ofboth ring-like means ateach-of.thei-respective pairs of aligned slots andtxvelded to saidrings, and :a slot in each .e; legof each ,clip having.- side 'walls aligned :with said: :wear. side. walls of ether-respective aligned 4" slots in the ring-like means.

4; iA non-rrotataole- -brake element for a disk brake-apparatus com-prising a ;pair;of., acoaxially' r arranged ring-like means arranged ;i.n,-loack tobackn'elation, .a 1' plurality 10f segmental brake shoes secured in spaced apartrelation to 63,012! of theioppositefacesnof nsaidi. pair of ringlike means a-plurality; of spaced.- apart-slots in, ca ofipthe-two -ring; 1ike; meansehaving opposite pa liclrw a -Wall ex ndin isen r iii, ofithering like; means ,and; .alig-nedwith :the weargr sides oisthe slots-in thesother ngria Cliflgfi tending pver --the opposite'isides; of; bothjring like, w means at each of therespectivepairaofialigned-i slots; and weldedrto said rings;. and .a islotain leaehc 1 I legaofeach. cl-ip having, sidewallsaligned-ninth 4 said-wean sidewalls oftherespectivexaligned-islotsin the, ring-likeemeans icertainof; said-,1 clip tending beyond. the: outer edge; of saidiorak el ment and vrcomprisingr;means forshifti i r"said1 0 brake element axiallyl M EMA nonerotatabla-brake :jiiSkgfOlFfl'diskhiiakfi'f.

apparatus .icomprising a -Ipai 10f750QaXiaiHyZ5; are" rangedring-like meansar-r-angedin back-to-backx.

relation, eachofsaidiring likarneanscomprising:

a plurality :of :disk segments, arranged i gin suhstantiall end-to end, relation,-. one or more dorake 1 shoes arranged one-the outer face of :ea,ch Se a-1 merit and; adjacent the winner gedge 5thereof,:: a bridgepiece overlying adj acentzends? of each adja cent -pa-ir:.-of segments andiwelded :thereto. exceptat;two'ponnectionsbetween two bridgepie'ces and 1 segmentsiarrangeddiametrically opposite on saids disks;:.-. each'i-;'of-:' said :bridge' pieces-- -having-two spaced-apart bor sior i-egryavith bores in"" iii; flyi .1e:segments;boltsv extendin thr ughiha=; aligned bores in :the two--bridge piecesjandseg,- mentsiarranged diametricallyopposite ,oi;thetwo;- IiI'IIr-likGT'IHCflHS rigidly securing, the two ring nd-segmentation welded together securing same; 5 like, nieansito each; other, a i plurality of spaced p'withthe wear sidesjof the -slot in the, otherringvlike means, a clip extending-fiver; theioppositeo sides; ofboth ring like-means at each of the re.-

spective pairs of aligned slots and. welded-thereto, andqa islot .-.in;each-1eg-;of each; clip having side;

' :walls aligned r-Jiththe'wear sidesof the respective slots-di -Vthe two ring like means;

eeAn:annulaixrotatable frictionklorake element forzza :diskxtype'aofvbrake' apparatus, comprisinga plurality ,of larcuate brake shoes arranged inga icircle ,ingspaced apart cnd-to end relation and; eaclrchaving a ;radially ,extending.; friction sur,-;- face adjacent its outer. edge, 7 torque meansxpro jecting radially inward-from the inner peripherala, edge of each shoe and having adriving surface arranged parallel, to a radius .of said brake, eler ment and-at right-angles to saidfriction surface a removable ring encircling the driving surfacesa; of the torque meanscand' encircled by, -the ,gfric tion' surfaces of the shoes, and, remoyablegmeans 7!; securing each torque. means andthereby-thererspective brake shoe to saidringagainstoutward movement by centrifugal; force.

'7. i An annularrotatable friction, brakeelementi a for a disk type of brake,apparatus,comprising-a plurality of arcuatebrake. shoes ,arrangediinsa 1 circle in a spaced- ,apart; end ato; endirelatiomand- 7 each having a radially; extendingirictionsuriace,. adjacentits outer edge; torque means projecting; radiallyinward fromqth-e-iinnerapcripheralsedge-'1 of each shoe and having a driving surfacegarep ranged parallel .to a radiuslof, said brake; element and atrright angles to. the respective friction sur,, face, a removable ring of less diameter .thanandarranged .icoax-ial, with the {friction surfaces of said shoes, each torquemeans.comprisingtwo-g spaced apart arcuatewalls arranged coaxial to the respective brakeshoe friction, surface and 1 defining a recess-to-receive saidring, and remov; ableemeans, securing; said ringin said recess ,of,-, each :torque means ofor holding V the,-,-respec tive torque -,means 1 and shoe. against :outward. movement-by centrifugal force.

8. An ,arcuate. brake, element for a rotor ,of a disl -bral e mechanism comprising an outershoce portion, having. on opposite faces.- paral-lelmare. ran ed radially, extendin -braking surfaCes,,-and.. an inner portion comprising torqueemeanslprow jectingradiaHy inward from the; inner peripheral edgeof said shoe-portion and'having a driving surfacearranged-parallel to a radius of said-shoe.-

portion and .at; right angles; to said brakin n sun-i faces, said inner portion comprising in onesidebetween; said i, driving surface, and, brakingi sur faces-;.a pair? of: spaced apart walls arranged ,co.- axial .withZthe, outer ,-;arc,uate edgeof saidshoe portionand defining opposite sides oi'ia irecess, extending.;;in the direction of the icircum-ference ofasaid rotor, and means defining a-bolt receiv ingxbore s-extendingothrough said inner portion opening a to said recess in:a direction paral-i :ingpa'rallelto the-"axis -of said member,- and "a rotatable friction brake element comprising a plurality of individual brake shoes arranged in end to end and spaced apart relation in a circle around said member and each comprising a pair of spaced apart torque lugs extending radially inwardly therefrom and disposed one on either side of and having driving connections with, respectively, opposite sides of one of said ribs, removable ring means encircling said member, and securing means removably securing each of said brake shoes to said ring means.

10. A disk brake apparatus comprising an annular rotatable element to be braked, a plurality of segmental brake elements encircling said rotatable element in spaced apart end to end relation and each having adjacent its outer edge a braking surface, said rotatable element and brake elements comprising cooperating driving means encircled by the braking surfaces of said brake elements for turning said brake elements with said rotatable element and removable means securing each brake element to said rotatable element against movement radially outward rela-- tive to said rotatable element.

11. A disk brake apparatus comprising an annular rotatable element to be braked, a plurality of segmental brake elements encircling said rotatable element in spaced apart end to end relation and each havin adjacent its outer edge a braking surface, said rotatable element and brake elements comprising cooperating driving means encircled by the braking surfaces of said brake elements for turning said brake elements with said rotatable element, a rin encircled by said braking surfaces and encircling said driving means and disposed in contact with said brake elements and removable means securing each brake element to said ring against movement radially outward relative to said rotatable element.

12. A disk brake apparatus comprising an annular rotatable element to be braked, a plurality of torque ribs spaced from each other around and projecting from the peripheral face of said element and extending parallel to the axi of said element, a plurality of segmental brake elements corresponding in number to said ribs and spaced apart in end to end relation in a circle around said rotatable element, each of said brake elements comprising a pair of spaced apart lugs projecting radially inward from the inner peripheral edge of the brake element and disposed one on either side of and in sliding contact with opposite sides of the respective torque rib, and removable means securing said brake elements against radial outward movement on the respective torque ribs.

13. A disk brake apparatus comprising an annular rotatable element to be braked, a plurality of torque ribs spaced from each other around and projecting from the peripheral face of said element and extending parallel to the axis of said element, a plurality of segmental brake elements corresponding in number to said ribs and spaced apart in end to end relation in a circle around said rotatable element, each of said brake ele ments comprising a pair of spaced apart lugs projecting radially inward from the inner edge of the brake element and disposed one on either side of and in sliding contact with opposite sides of the respective torque rib, a ring encircling said torque'ribs and encircled by said brake elements, and removable means securing each of said brake elements to said ring.

14. A disk brake apparatus comprising an annular rotatable element to be braked, a plurality of torque ribs spaced from each other around and projecting from the peripheral face of said element and extending parallel to the axis of said element, a plurality of segmental brake elements corresponding in number to said ribs and spaced apart in end to end relation in a circle around said rotatable element, each of said brake elements comprising a pair of spaced lugs projecting radially inward from the inner edge of the brake element and disposed one on either side of and in sliding contact with opposite sides of the respective torque rib, a ring encircling said torque ribs, each of said brake elements having an arcuate recess adjacent the respective lugs for receiving said ring, and removable means securing said ring to each brake element within said recess.

15. A disk brake apparatus comprising an annular rotatable member to be braked, a plurality of ribs extending parallel to the axis of said member and arranged in spaced apart relation, said member also having a plurality of spaced apart slots arranged parallel to said ribs, a rotatable friction brake element slidably mounted on said ribs and having a brake release position, a plurality of spaced apart fingers on said brake element extending into certain of said slots, a spring in each of said certain slots acting on the respective finger for urging said brake element to said brake release position, a removable stop in each of said certain slots engageable by said fingers for definin said release position, said rotatable member having in each rib a circumferentially extending groove aligned with the grooves in the other ribs and each of said stops having a recess for circumferential alignment with the grooves in the adjacent ribs, and a removable ring encircling said member and disposed in said grooves and recesses for holding said stops in said rotatable member.

16. A disk brake apparatus comprising an annular rotatable member to be braked, a plurality of spaced apart ribs arranged around said member and extending parallel to the axis thereof and each rib having a slot extending parallel to the rib, a brake shoe for each rib slidably mounted thereon, ring means encircling said member and comprising a plurality of spaced fingers disposed in certain of said slots, one bolt securing each brake shoe to said ring means for rendering said ring means effective to hold the brake shoes in spaced relation, a removable ring encircling said member disposed in recesses in said ribs for engagement by said fingers to define a brake release position of the shoes, a spring follower in each of said certain slots engaging the respective finger, a spring disposed under pressure in each of saidcertain slots acting on the respective follower for urging the respective finger into engagement with said ring, and a removable element extending into each of said certain slots for engagement by the respective followers to hold them and the respective springs in the slots upon removal of said ring.

1'7. A disk brake apparatus comprising an annular rotatable member to be braked, a plurality of spaced apart ribs arranged around said member and extending parallel to the axis thereof and each rib having a slot extending parallel to the rib, a pair of annular rotatable brake elements encircling said ribs and spaced apart axially and each comprising a brake shoe having torque lugs slidably engaging the sides of one of said ribs, ring means encircling said member, a

13 bolt securing each brake shoe to said ring means, a plurality of spaced apart fingers projecting inwardly from said ring means, the fingers of one of said brake elements being disposed in certain of said slots and the fingers of the other brake element being disposed in the other slots, each of said ribs having a circumferentially extending groove aligned circumferentially with the grooves in the other ribs, a removable ring encircling said member disposed in all of said grooves, a spring in each of said certain slots acting on the fingers therein for urging them into engagement with said ring to define a brake release position of the respective brake element, a removable stop in each of said other slots having a recess to receive said ring for holding the stop in the slots, and a spring in each of said other slots act- 14 ing on the respective fingers for urging them into engagement with the respective stop for defining a brake release position of the respective brake element.

JOSEPH C. McCUNE.

References Cited m the file of this patent UNITED STATES PATENTS Number Name Date 1,683,806 Richards Sept. 11, 1928 2,277,106 Hewitt Mar. 24, 1942 2,284,253 Baselt et a1 May 26, 1942 2,318,620 Nutt May 11, 1943 2,423,881 Du Bois July 15, 1947 2,485,082 Bachman Oct. 18, 1949 

